In video and/or multimedia terrestrial transmission systems, such as cable television systems ("CATV"), it is desirable to evaluate the integrity of the transmission lines that carry signals between distribution offices and end users/subscribers. Such integrity evaluations may be performed on a periodic basis to gauge the overall reliability of the transmission system, or can be targeted to specific lines in response to a particular service problem. Naturally, to minimize inconvenience to users of the transmission system it would be advantageous to perform such evaluations in a manner that does not disrupt the transmission and reception of signals normally carried via the lines being evaluated.
Presently, CATV providers locate line integrity problems by investigating customer complaints. That is, in response to receiving one or more complaints from subscribers that service is less than optimal, a locus for the likely problem is found, and service personnel dispatched to check the line or lines in question. In typical cable video/multimedia distribution systems there exists no ready means for performing a test of a particular connection between a central distribution office and one or more remote nodes or subscriber premises, and certainly no means to provide real-time feedback showing the result of such a test.